I guess on one level this is suprising.

Lesbian "marriages" more likely to end in divorce:

Lesbian Divorce Shocker: Same-sex marriages between women are considerably more likely to end in divorce than either same-sex male marriages or heterosexual marriages, according to a study of Norway and Sweden:

We found that divorce risks are higher in same-sex partnerships than in opposite-sex marriages, and that unions of lesbians are considerably less stable, or more dynamic, than unions of gay men. In Norway as well as in Sweden, the divorce risk in female partnerships is practically double that of the risk in partnerships of men.

Is the difference explained by a relative lack of children to encourage stability? Maybe not. The study found a similar pattern with childless couples (when other variables were accounted for).

So what’s the explanation? Here’s the murky PC theory offered by the study’s authors:

We find that partnerships of women to a much larger extent are demographically homogamous than are partnerships of men: Lesbian partners often have relatively similar characteristics while gay spouses more often differ in terms of characteristics such as age, nationality, education, and income. Such similarity in characteristics might also reflect a deeper feeling of sameness in lesbian couples. Such a sameness and a corresponding lack of clear power structures may be inducive to a high level of dynamism in the relationship, but perhaps not to the kind of inertia that is related to marital stability. [E.A.]

Um, ok. … You got a better explanation? …

Backfill: The study is not new–it appears to have been published in 2006. It’s new to me.

Or there is Glen Reynolds' explanation:

LESBIAN DIVORCE SHOCKER: Same-sex marriages between women are considerably more likely to end in divorce than either same-sex male marriages or heterosexual marriages, according to a study of Norway and Sweden. Well, women initiate divorce twice as often as men, so it stands to reason that a marriage composed of nothing but women would be more likely to split.

Makes sense: if women are twice as likely to initiate divorce in real marriages, then its stands to reason that the women in a lesbian marriage would be four times as likely to initiate divorce.

Yeah, I know it really doesn't work that way, but do you have a better explanation?